This invention relates to a color picture tube, and more particularly to that type whose phosphor screen has its color reproducibility noticeably improved. The most important characteristics of a color picture tube are represented by color brightness, color contrast and the purity or reproducibility of each of the green, blue and red colors. These characteristics largely depend on the light-emitting property of a phosphor material. To date, however, no combination of blue, green and red color-emitting phosphor materials has been developed which can fully realize the aforementioned characteristics. Hitherto, phosphor materials have been selected with most importance attached to the brightness of their colors. A known phosphorescent assembly providing the brightest phosphorescent screen is represented by a combination of a green-emitting phosphor ZnS: Cu, Au, Al, a blue-emitting phosphor ZnS: Ag, Cl and a red-emitting phosphor Y.sub.2 O.sub.2 S: Eu. Except for the blue-emitting phosphor ZnS: Ag, Cl, the green and red-emitting phosphor cannot be considered to give a sufficient color purity. To elevate the brightness of a red-emitting phosphor, it is possible to use a slightly orange-tinged red phosphor. In this case, it is possible to obtain a sufficiently bright white picture by mixing a slightly yellowish green-emitting phosphor with the above-mentioned orange-tinged red phosphor. However such attempt is accompanied with a loss of hue and saturation thus failing to ensure faithful color reproducibility. Further, a red phosphor having deep saturation is too reduced in brightness for practical application.